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jm3000x
10-21-2008, 03:59 PM
I have a question I was hoping someone could help out with on the difference between series and parallel plate configuration. I've read where series setups run cooler, and don't produce as much HHO as parallel, but what exactly is the difference? Assuming all plates are within the same generator, and receive current through two sections of SS allthread, would
+NNNNN--NNNNN+ and +NNNNN- +NNNNN- both be considered series configs? If so, what would an example of a parallel configuration look like?
Thanks!

mytoyotasucks
10-22-2008, 03:53 PM
I have a question I was hoping someone could help out with on the difference between series and parallel plate configuration. I've read where series setups run cooler, and don't produce as much HHO as parallel, but what exactly is the difference? Assuming all plates are within the same generator, and receive current through two sections of SS allthread, would
+NNNNN--NNNNN+ and +NNNNN- +NNNNN- both be considered series configs? If so, what would an example of a parallel configuration look like?
Thanks!

in series u are using 12V divided by the number of cells

in parallel u are giving each cell 12V

series 4 cells(C) CCCC/12V=3V per cell
parallel 4 cells CCCC and still have 12V per cell

jm3000x
10-23-2008, 08:01 AM
So multiple cells within the same generator split the supply voltage and are considered a series setup.

mytoyotasucks
10-23-2008, 01:20 PM
So multiple cells within the same generator split the supply voltage and are considered a series setup.

yes, that is why most people put them in parallel

or series in a plexiglass multi cell setup, where each cell has two or three plates each.

jm3000x
10-24-2008, 04:36 AM
I've read that the most efficient design is around 1.4-2V per cell in a series design, but with input voltage of 13.8V and a plate configuration like +NNNNNN- using around 3% NaOH with 3x5" plates, I get very little production (like 300ml/min @ around 14A). The only way I've been able to get moderate output is running around 3.5V per cell - but this brings up heat problems. This is in a wet generator with the sides wrapped and the top and bottom open for gas to escape. Is there something I'm neglecting, or does it usually take a couple sets of cells in parallel to get any volume?

mytoyotasucks
10-24-2008, 04:45 AM
I've read that the most efficient design is around 1.4-2V per cell in a series design, but with input voltage of 13.8V and a plate configuration like +NNNNNN- using around 3% NaOH with 3x5" plates, I get very little production (like 300ml/min @ around 14A). The only way I've been able to get moderate output is running around 3.5V per cell - but this brings up heat problems. This is in a wet generator with the sides wrapped and the top and bottom open for gas to escape. Is there something I'm neglecting, or does it usually take a couple sets of cells in parallel to get any volume?

actually i found that +NNNNN- works really great and plate voltage is around 2.25v each.

I have found eventhough they say it starts around 1.4V - IT DOSEN'T, just like u found out.

and for more production, u need more amps, i run from 18A for a 4 plate setup to 35A with a 7 plate setup, still going to try different plate gaps and a 5 and 6 plate setup.

but it does look like ur headed in the right direction - experimenting is good - that is how things are figured out.

keep me posted, and ill do the same.

mytoyotasucks
10-24-2008, 04:55 AM
I should also note:
1 - stay away from tapes to wrap a cell or straps - they will give u a orange or brown tinge - adheasive gets eaten.
2 - when experimenting u will use more KOH than people say u will use, already went through a pound of KOH and 2 pounds of sodium hy.
3 - I use shrink wrap for wraping cells, i first tape the cells together, than put some shrink wrap on to hold together, and than take tape back off and put another layer of shrink wrap - holds nice and tight.

- if i can think of anymore i will post later - (i want to star to take notes to pass on to others like in the hhowiki some else on the forum is puting together).

4 - dont put a flame to the bottle u just used to test LPM - it goes BOOM!! - been there done that. LOL

Painless
10-24-2008, 08:40 AM
I have found the following to be true in my experiments:

1) Best production is at approx 2.3v per cell. My dry cells use +NNNNN- at 14.1v.

2) The larger the gap, the more volts per cell or higher electrolyte concentration will be needed. I advise 1/16" or smaller.

3) Dry cell designs, while they present their own design challenges, are far superior to open baths. In return, you get controlled heat (and henceforth amperage), good MMW efficiency and a much smaller generator.

Good luck in your experiments, sharing is the key!

Feel free to make use of my wiki, that's what I built it for.

Russ.

mytoyotasucks
10-24-2008, 01:34 PM
I have found the following to be true in my experiments:

1) Best production is at approx 2.3v per cell. My dry cells use +NNNNN- at 14.1v.

2) The larger the gap, the more volts per cell or higher electrolyte concentration will be needed. I advise 1/16" or smaller.

3) Dry cell designs, while they present their own design challenges, are far superior to open baths. In return, you get controlled heat (and henceforth amperage), good MMW efficiency and a much smaller generator.

Good luck in your experiments, sharing is the key!

Feel free to make use of my wiki, that's what I built it for.

Russ.

now i know im on the right track. and i am using 1/6" spacing (just checked).

and dry cells are on my to-do list, but was still experimenting with wet cells.

M Bell
10-24-2008, 02:13 PM
I have to agree with JM300x. I have found that you get much better production with a 3.2 to 3.9 volts per cell repete. I have tried numerous cell configurations. With the voltage less than 3 volts the amperage stays to low and the output stays low. I have a dual dry cell setup that is set up +nn-nn+ Paralleled with +nn-nn+. I am running 25.5 amps at 12.5 volts. I am getting 1.5 lpm. I use distilled water with naoh. Very little naoh. The plates in my cell are 4in x 5in.

mytoyotasucks
10-24-2008, 02:45 PM
I have to agree with JM300x. I have found that you get much better production with a 3.2 to 3.9 volts per cell repete. I have tried numerous cell configurations. With the voltage less than 3 volts the amperage stays to low and the output stays low. I have a dual dry cell setup that is set up +nn-nn+ Paralleled with +nn-nn+. I am running 25.5 amps at 12.5 volts. I am getting 1.5 lpm. I use distilled water with naoh. Very little naoh. The plates in my cell are 4in x 5in.


OK if ur amps stay low - than add more NaOH, amps will come up.


i dont condone the use of NaOH (bad mojo)

ShowMeHHO
10-24-2008, 03:18 PM
I have to agree with JM300x. I have found that you get much better production with a 3.2 to 3.9 volts per cell repete. I have tried numerous cell configurations. With the voltage less than 3 volts the amperage stays to low and the output stays low. I have a dual dry cell setup that is set up +nn-nn+ Paralleled with +nn-nn+. I am running 25.5 amps at 12.5 volts. I am getting 1.5 lpm. I use distilled water with naoh. Very little naoh. The plates in my cell are 4in x 5in.

What is the temp of your electrolizer @ 25.5 amps at 12.5 volts getting 1.5 lpm .
In trying diferant configurations with 7 plates I got good results with
-nn+nn- less Naoh and instant results .I am still trying to get the +nnnnn_ to work but it starts out reall low on amps with hardly any production untill it warms up then it wants to run away .Now this is in a bay setup so I think with the 5 neautrals in the middle I am loosing more off the edges into the bay than with the other configuration ...

HALS-GUNSMITHING
10-24-2008, 05:32 PM
I have a feeling that the conductivity of the plates have a lot to do with the optimum voltage per cell. S.S. is a poor conductor when compared to copper and aluminum which should not be used for HHO. I think the S.S. is acting like a resistor, requiring more volts per cell (2 - 3 volts). Just my own theory.

mytoyotasucks
10-24-2008, 08:14 PM
I have a feeling that the conductivity of the plates have a lot to do with the optimum voltage per cell. S.S. is a poor conductor when compared to copper and aluminum which should not be used for HHO. I think the S.S. is acting like a resistor, requiring more volts per cell (2 - 3 volts). Just my own theory.

well i hope when they talk about volts, they arnt talking about platinum - nobody can afford that, even though its the best material.

alpha-dog
10-25-2008, 03:48 PM
I have a question I was hoping someone could help out with on the difference between series and parallel plate configuration. I've read where series setups run cooler, and don't produce as much HHO as parallel, but what exactly is the difference? Assuming all plates are within the same generator, and receive current through two sections of SS allthread, would
+NNNNN--NNNNN+ and +NNNNN- +NNNNN- both be considered series configs? If so, what would an example of a parallel configuration look like?
Thanks!

a series cell is +NNNNN-
a parallel cell is +-+-
a series/parallel is +NNNNN-NNNNN+
Russ

jm3000x
10-25-2008, 04:20 PM
Experimented with multiple setups and recorded the results at startup - after I compile the data I will post the results later this weekend. I found some interesting configurations produce more than expected...

mike915
08-03-2010, 01:14 PM
in series u are using 12V divided by the number of cells

in parallel u are giving each cell 12V

series 4 cells(C) CCCC/12V=3V per cell
parallel 4 cells CCCC and still have 12V per cell

Sorry but i still don't understand the difference...

a series cell is like this? -NNNNN+NNNNN- together?
and a parallel is like this? (-NNNNN+) (-NNNNN+) separate?

so which voltage would have each example per gap?
and which one is more efficient??

myoldyourgold
08-03-2010, 01:55 PM
http://www.hhoforums.com/showthread.php?t=5328&highlight=calculate+voltage&page=61

HHOJeeper
08-18-2010, 08:22 PM
My last Generator and the design I want to use on a larger scale was -NNNN+NNNN-. For the test, mainly due to available metal, my plates were 3.5 in by 3.5 in. With 1.5x1.5 in. squared reactive plate area. Running it in the Jeep my mileage dropped 3-4 mpg. What I want to do is run 2 such 11 plate stacks where both generators are wired in parallel to each other so they produce double the output of a single gen/stack and are hooked to 1 reservoir. Would the amperage double as well?

myoldyourgold
08-18-2010, 08:44 PM
My last Generator and the design I want to use on a larger scale was -NNNN+NNNN-. For the test, mainly due to available metal, my plates were 3.5 in by 3.5 in. With 1.5x1.5 in. squared reactive plate area. Running it in the Jeep my mileage dropped 3-4 mpg. What I want to do is run 2 such 11 plate stacks where both generators are wired in parallel to each other so they produce double the output of a single gen/stack and are hooked to 1 reservoir. Would the amperage double as well?

Is the 1.5 x 1.5 active area correct. That is very small and would limit you to much.

Follow these three rules and you will be fine.

1. Not MORE than .5 amps/in² of active surface area on ONE plate.

2. Not MORE than 2.3 volts/cell (gap).

3. Not more than 500 ml/liter of engine size. Some engines require slightly more.

HHOJeeper
08-22-2010, 09:00 PM
Yeah, 1.5x1.5. Thing was super small. Like I said had a small amount of metal to work with. I had a free sheet of steel 12"x6" that I cut into 12 pieces and used 11 of them.

myoldyourgold
08-22-2010, 09:56 PM
Jeeper Sir, That is to small to work with. You should only be running 1 amp through that to be safe. When you run more than that you are basically making a boiler. Not good at all. You must have larger surface area to make enough gas with out making a lot of steam which will carry a lot of electrolyte with it and possibly cause damage to your engine. Follow the rules I posted and that will give you a good start. You can then adjust from there.

hhojedi
08-23-2010, 07:22 PM
Is the 1.5 x 1.5 active area correct. That is very small and would limit you to much.

Follow these three rules and you will be fine.

1. Not MORE than .5 amps/in² of active surface area on ONE plate.

2. Not MORE than 2.3 volts/cell (gap).

3. Not more than 500 ml/liter of engine size. Some engines require slightly more.

great info, i like the peramiters, gives a good jumping off point to get me started in the right direction, thanks for sharing your knowledge.
would this hold true for wet and dry cells, or did you have one or theother in mind? i'm about to start a new gen. and i want to try and size things better than just guessing like my first design.

peace

jedi

myoldyourgold
08-23-2010, 10:18 PM
I would not build a wet reactor. So apply it to dry reactors.

HHOJeeper
08-30-2010, 09:27 PM
Jeeper Sir, That is to small to work with. You should only be running 1 amp through that to be safe. When you run more than that you are basically making a boiler. Not good at all. You must have larger surface area to make enough gas with out making a lot of steam which will carry a lot of electrolyte with it and possibly cause damage to your engine. Follow the rules I posted and that will give you a good start. You can then adjust from there.

I produced hardly any steam at all. Then again I was running hardly any E at first too.
gen;
http://www.youtube.com/watch?v=MfgjZsGvEPk

I have videos of it running but for some reason I cannot send them from my phone

sunjay
12-02-2010, 05:43 AM
yes the entire process is based upon parell and series operations only...
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Farrahday
12-05-2010, 07:56 AM
Is the 1.5 x 1.5 active area correct. That is very small and would limit you to much.

Follow these three rules and you will be fine.

1. Not MORE than .5 amps/in² of active surface area on ONE plate.

2. Not MORE than 2.3 volts/cell (gap).

3. Not more than 500 ml/liter of engine size. Some engines require slightly more.

Hi, I've only recently found this forum, and (apart from The Water Fuel Cell Forum, which is primarily Meyer focussed, and WaterFuelforAll which has recently died a death) as far as I'm aware this is the only forum dedicated to the production of on-demand hydroxy, which is my field of expertise. I'm a member of many of the other OU forums, but there is little interest or indeed experience specifically in Electrolysers amd Hydroxy. So this it would seem is the place to be.

Can I just ask how you came by this set of 'rules'?

The significance of the voltage across each cell is obvious, but not so the other factors you state. For instance, what do you see happening if you draw, say, 2 amps per square inch of electrode?

There seems to be an awful lot of confusion here regarding plate configurations, etc, when quite simply we are looking to drop about 2 volts across each individual cell. In theory around 1.27 volts should do the trick, but adding electrolytes, plate materials and other factors make 2 volts a fairly safe figure.

Of course the idea is to achieve the minimum voltage to initiate electrolysis, while maximising the current. Any voltage above the threshold needed to initiate electrolysis, will increase power dissipation. It will of course also increase the gas output, but ideally we would want the extra current drawn due to lower resistance of the cells rather than increased voltage across them.

So if planning to use on a 12 vehicle, an electrolyser consisting of 7 plates in series is what you are looking at. You can then add further set of 7 plates electrolysers in parallel to this to enhance gas output.

It is always worth bearing in mind the relationship between Voltage, Current and Resistance, as per Ohms Law: V = I x R

Incidentally, though electrolytes add ion charge carriers and so reduce the resistance of the cells, because they themselves do not actually take part in the reaction at the electrodes, electrolytes will infact reduce overall cell/electrolyser efficiency.

Of course adding electrolyte is not the only way to reduce the resistance of the cells. Spacing the electrodes closer together or increasing the surface area of the electrodes also does the trick.

myoldyourgold
12-07-2010, 09:11 AM
Can I just ask how you came by this set of 'rules'?

Farrah, the rules I stated are starting points for a beginner. Rules are made to brake in my book. As far as where they came from some are experience and others are from scientific research that has been published.

Not MORE than .5 amps/in² of active surface area on ONE plate comes from a study that found that 700 a/m² was the optimal current density. .5 amps is close a bit over I think, I did not do the math. I found everything worked better keeping it under .5 amps and this is in 1000's of hours or run time and still counting. I am running at .47 a/in² which seams to be the sweet spot in my set up.

Farrahday
12-08-2010, 02:17 AM
Okay, fair enough. So cross hatching the plates should greatly increase plate surface area and hence increase the figure of '0.5 amps/in² of active surface area on ONE plate', assuming of course that this has not already been taken into consideration.

I know that electroplating currents certainly do dictate the nature of the deposits in terms of quality and reliability, so it does make sense that there will be an optimum current flowing through the cell for any given plate surface area, though what this means in terms of an electrolyser just evolving gases is not entirely clear. There may be some element of charge 'gridlock' occurring if we try to draw too much current through a cell with not enough plate surface area. Interesting.

myoldyourgold
12-08-2010, 07:50 AM
Media blasting works a lot better than cross hatching and gives you much more surface area and much finer bubbles. Production increases heat goes down. Small bubbles prevent hot spots on the plates, lowers resistance, bubbles release faster and the production of Cr6 is reduced when using stainless. It is critical to make sure every plate is exactly the same. Things are a lot different when using nickle plates or a combination of nickle and stainless. Testing is on going in this area.

All of this changes the formula as far as optimum resistance per square inch. Each reactor is different and one most be able to tune it by controlling the electrolyte as I am not a PWM person. Measuring temperature accurately and production is critical to find the sweet spot. There is a definite sweet spot which can be found with some effort. The whole object for me is to get the amps down and the production up with a gas that works with the cars ECU without the use of electronics. It is a challenge but has been done just needs simplifying so it can be duplicated easily every time and under different conditions. Some cars are more of a challenge than others and results vary.

bobsbbq
02-16-2011, 10:06 PM
Media blasting works a lot better than cross hatching and gives you much more surface area and much finer bubbles. Production increases heat goes down. Small bubbles prevent hot spots on the plates, lowers resistance, bubbles release faster and the production of Cr6 is reduced when using stainless. It is critical to make sure every plate is exactly the same. Things are a lot different when using nickle plates or a combination of nickle and stainless. Testing is on going in this area.

All of this changes the formula as far as optimum resistance per square inch. Each reactor is different and one most be able to tune it by controlling the electrolyte as I am not a PWM person. Measuring temperature accurately and production is critical to find the sweet spot. There is a definite sweet spot which can be found with some effort. The whole object for me is to get the amps down and the production up with a gas that works with the cars ECU without the use of electronics. It is a challenge but has been done just needs simplifying so it can be duplicated easily every time and under different conditions. Some cars are more of a challenge than others and results vary.

Would using a sand blaster work instead of cross hatching or is this to much?

Bhart
02-17-2011, 02:17 PM
Yes, the preferred method is sand blasting over glass beads, and cross sanding.